Formation testing tool



O. F. CUTRIGHT FORMATION TESTING TOOL Filed July l2, 1954 irma/5K5FORMATION TESTING TOOL Olie F. Cntr-ight, Sidney, Nehr., assignor, bymesne assignments, to Johnston Testers, Inc., Houston, Tex., acorporation of Texas Application `luly 12, 1954, Serial No. 442,645

2 Claims. (Cl. 166-151) This invention relates to oil well tools, andparticularly to an improvement in a formation testing tool ofthecharacter disclosed in the copending application of Jack A. Moosmanentitled Hydraulic Valve Device, filed February 3, 1953, and bearingSerial No. 334,889, both this application and said copending applicationbeing assigned to the same assignee.

The above identified copending application includes a packer adapted tobe set in a well bore to separate the formation zone from the well fluidthereabove, valves for controlling upward ilow of theconnate uid in thetool, and an equalizing valve to allow well iluid to bypass the packerand equalize the pressure above and below the packer before unseatingthe same. It has been found that in some instances the packer becomesstuck in the well bore and great diiiiculty is encountered in trying toremove the tool from the well bore, even after pressures havebeenequalized.

It is, therefore, the principal object of this invention to provide aformation testing tool of the type set forth above wherein an inwardlyopening check-valve is provided in the equalizing ports above the packerwhereby fluid may be pumped down through the tool and underneath thepacker to aid in freeing the packer.

Various other objects of the instant invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings, wherein:

Figs. 1, 2 and 3 are longitudinal views partly in-section of the upper,middle and lower portions, respectively, of a tool embodying theconcepts of the present invention, showing the same in its running-in orcoming-out condition.

Fig. 4 is a horizontal sectional view taken along line 4 4 of Fig. 2.

Referring to the accompanying drawings, wherein similar referencecharacters designate similar parts throughout, there is disclosed a toolembodying the concepts of the present invention including a compositetubular mandrel, generally indicated at 10, slidably received within acomposite tubular housing, generally indicated at 11, said housing beingconnected at its lower end. to a tool section 12 carrying a packer 13and a perforated section 14 through which connate uid may enter thetool. At its upper end the mandrel has a sub 15 for attachment to thelower end of a string of pipe 16, by which the tool may be run into awell bore.

The housing 11 includes four tubular sections 17, 18, 19 and 20, readingfrom top to bottom, said sections being threadedly connected inend-to-end relation as shown, the lower section 20 having dependingtherefrom a sub 21 for attachment to the tool section 12. The mandrel1i) comprises three sections 22, 23 and 24 threadedly connected inend-to-end relation, the upper section being connected to the sub 15,previously mentioned. The top housing section 17 slidably receives theupper mandrel section 22 at its upper end and is non-rotatably connectedto said mandrel section 22 by keyways 25 provided on said i nited StatesPatent O housing section slidably receiving keys 26 provided on themandrel section 22.

A piston 27 is formed on the lower end of the mandrely section 22 and isslidably received within a liquid-filled` cylinder 28 provided in thehousing section 17. Appropriate sealing means 29 and 30 are provided onthe pis.- ton 27 and are disposed in sealing engagement with the wallsof the cylinder 28 and the exterior of the mandrel section 23,respectively. The liquid in the cylinder 28 is adapted to beforcedtherefrom through a meteringforitce arrangement 31 into areservoir 32 provided in the housing section 18 upon downward movementof themandrel:

10' relative to the housing 11. The upper end of the,

housing section 18 slidably engages the mandrel section` 23, and anO-ring seal 33 carried by the housing sectionl 1S prevents leakage fromthe cylinder 28 into the reservoir 32 other than through the orificearrangement 31. A floating piston 34 is slidably disposed within thereservoir- 32 and sealingly engages the walls of the reservoir 32,bymeans of an O-ring seal 35 and the exterior of mandrel section 23 bymeans of an O-ring seal 36. The reservoir 32 communicates with theexterior of the housing 1'1 by means of ports 37 formed in the walls ofthe housing section 18.

It is apparent that the metering orifice arrangement 317 functions toretard downward telescopic movement of the mandrel 10 within the housing11. An upwardly opening check valve arrangement 38 is provided in theupper end of the housing section 18 and communicates.l

on its lower side with the reservoir 32 through a relatively largediameter passageway 38a and on itsupper side with the cylinder 28 toallow ready upward movement ofthe mandrel 10 relative to the housing 11.

The lower end of the mandrel section 23 is slidably received in theupper end of the housing section 19, there being an O-ring seal 39 onthe housing section sealingly engaging said mandrel section 23. Connatefluid ports 40` are formed in the walls of the mandrel section 23,andare initially closed and covered by the opposing walls ofthe housingsection 19. The housing section 19 carries a.

,packing 41 which sealingly engages the mandrel section 24. A packinggland 42 threadedly received by the housing section 19 functions toretain the paekingftl in place, The packing gland 42 is counterbored toprovide a recess. 43 within which the connate uid ports 40 can beproject-y `ed and exposed. Longitudinal passages 4Sare formed in thehousing section 20 and communicate withthe recess. 43 at their upperends and at their lower ends with the;

interior of the sub 21.

Equalizing ports 46 are formed in the walls -of the mandrel section 24,and an annular recess 47 is formed in the housing section 2t) initiallysurrounding said ports. The

annular recess 47 communicates with the exterior 0f the housing 11 bymeans of passages or ports.48, see Fig; 4.' Each of the ports 48 has aninwardly opening check.. valve assembly 49 mounted therein. The checkvalve assembly 49 comprises a spider 50 having an external flange 51thereon slidably received in a counterbored portion 52 of the port 48,and held therein by an annular nut 53 threaded into the outer end ofsaid counterbored portion 52 and abutting the outer surface of theflange 51. The spider 50 has a plurality of passages 54 formed thereinto permit fluid to pass therethrough. The inner end of the spider 50 isformed with an annular beveled seat 55 which is adapted to receive acomplementary formed surface on the head 56 of a poppet type valve 57.The stem 58 of the valve 57 is slidably received in a central bore 59 inthe spider 50. When fluid is passing inwardly through the valveassembly, the valve 57 is prevented from coming out of the spider 50 bythe head 56 thereof abutting the outer surface of the mandrel section24.

Sealing means 60 and 61 carried by the housing section Patented Aug.2.8, 19.56.-

20 seaiingly engage the mandrel section 23 above and below theequalizing ports 46, the latter sealing means 61 assuming the form ofpacking and being retained in place by a packing gland 62. It isapparent that the distance of downward movement of the mandrel necessaryto cover the ports 46 (i. e. dispose the ports within the packing 61) issubstantially less than that necessary to uncover the connate fluidports 40.

A downwardly opening check valve 63 is provided in the central passagethrough the mandrel 10 between the connate iluid ports 40 and theequalizing ports 46. A spring 64 normally urges said valve upwardlytoward its closed position.

The operation of the tool is as follows: With the elements of the toolin the positions shown in Figs. 1, 2 and 3, the tool is run into thewell by being suspended from a string of pipe 16 and the packer 13 isset. As the weight of the string of pipe is partially imposed on themandrel 10, the piston 27 is forced slowly downwardly, forcing thehydraulic Huid within the cylinder 28 through the metering oricearrangement 31 into the reservoir 32. This action forces the piston 34downwardly and the well fluid within the reservoir out through the ports37.

As the mandrel 10 is moved downwardly, the equalizing ports 46 will rstbe closed, and thereafter, after considerable movement of the mandrel,the connate uid ports 40 will be brought into registry with and `exposedwithin the recess 43. Consequently, connate fluid may flow up throughthe perforated section 14, through the passages 4S, into the recess 43,through the ports 40 and upwardly into the string of pipe 16.

After the sample has been taken, the string of pipe 16 may be pulledupwardly. This action draws the piston 27 upwardly, such movement beingreadily permitted because the hydraulic fluid disposed in the reservoir32 is allowed to freely pass upwardly through the large diameterpassageway 38a and the check valve arrangement 38. Well uid entersbehind the piston 34 so that movement of said piston is not retarded.This upward movement functions first to cover the connate fluid ports 40and thereafter expose the equalizing ports 46 within the annular recess47 to permit the fluid in the well bore to ilow past the check valveassemblies 49 and pass downwardly through the tool to equalize thepressure above and below the packer 13. Fluid is then pumped downwardlythrough the well string 16 and the check valve 63. Since the uid cannotpass :outwardly through the ports 38 because of the check valveassemblies 49, the fluid flows outwardly through the perforated section14 and applies pressure to the bottom of the packer 13 to aid inunseating the same. When the packer is unscated, upward movement of thetool is readily permitted because the well fluid above the packer canreadily pass inwardly through the ports 48, the equalizing ports 46, anddownwardly through the tool and out through the perforated section 14 tothereby bypass packer 13.

By the present invention, a novel formation tool has been providedwhereby pressure may be pumped down through the well string to aid inunseating the packer.

While I have shown the preferred form of my invention,

it is to be understood that various changes may be made in itsconstruction by those skilled in the art without departing from thespirit of the invention as dened in the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

l. In a formation tester adapted to be lowered into a Well bore on astring of well tubing, a housing, a packer on said housing adapted to beseated in the well bore, a plurality of lateral bypass ports in saidhousing above said packer, a mandrel slidably mounted in said housing insealing engagement therewith above and below said bypass ports, alongitudinal passageway in said mandrel connected at its upper end withthe interior of said well string and at its lower end with the interiorof said housing below said packer, a plurality of bypass ports in saidmandrel connecting said longitudinal passageway with the exterior ofsaid mandrel, said mandrel bypass ports being adapted to be brought intoregister with said housing bypass ports by longitudinal movement of saidmandrel relative to said housing, and an inwardly opening check valve ineach of said housing bypass ports, whereby fluid is permitted to passinwardly through said housing bypass ports and Iout the bottom of thetool to equalize the pressure above and below said packer, and wherebyuid may be pumped down through said string of well tubing and out of thebottom of said tool to apply pressure to the bottom of said packer toaid in unseating the same without passing outwardly through said housingbypass ports.

2. In a formation tester adapted to be lowered into a well bore on astring of well tubing, a housing, a packer on said housing adapted to beseated in the well bore, a plurality of lateral bypass ports in saidhousing above said packer, a mandrel slidably mounted in said housing insealing engagement therewith above and below said bypass ports, alongitudinal passageway in said mandrel connected at its upper end withthe interior of said well string and at its lower end with the interiorof said housing below said packer, a plurality of bypass ports in saidmandrel connecting said longitudinal passageway with the exterior ofsaid mandrel, said mandrel bypass ports being adapted to be brought intoregister with said housing bypass ports by longitudinal movement lofsaid mandrel relative to said housing, and an inwardly opening poppettype check valve in each of said housing bypass ports, whereby fluid ispermitted to pass inwardly through said housing bypass ports and out thebottom of the tool to equalize the pressure above and below said packer,and whereby fluid may be pumped down through said string of well tubingand out of the bottom of said tool to apply pressure to the bottom ofsaid packer to aid in unseating the same without passing outwardlythrough said housing bypass ports.

References Cited in the le of this patent UNITED STATES PATENTS1,905,208 Badgett Apr. 25, 1933 1,980,219 Morris Nov. 13, 1934 2,073,107Johnston Mar. 9, 1937

1. IN A FORMATION TESTER ADAPTED TO BE LOWERED INTO A WELL BORE ON ASTRING OF WELL TUBING, A HOUSING, A PACKER ON SAID HOUSING ADAPTED TO BESEATED IN THE WELL BORE, A PLURALITY OF LATERAL BYPASS PORTS IN SAIDHOUSING ABOVE SAID PACKER, A MANDREL SLIDABLY MOUNTED IN SAID HOUSING INSEALING ENGAGEMENT THEREWITH ABOVE AND BELOW SAID BYPASS PORTS, ALONGITUDINAL PASSAGEWAY IN SAID MANDREL CONNECTED AT ITS UPPER END WITHTHE INTERIOR OF SAID WELL STRING AND AT ITS LOWER END WITH THE INTERIOROF SAID HOUSING BELOW SAID PACKER, A PLURALITY OF BYPASS PORTS IN SAIDMANDREL CONNECTING SAID LONGITUDINAL PASSAGEWAY WITH THE EXTERIOR OFSAID MANDREL, SAID MANDREL BYPASS PORTS BEING ADAPTED TO BE BROUGHT INTOREGISTER WITH SAID HOUSING BYPASS PORTS BY LONGITUDINAL MOVEMENT OF SAIDMANDREL RELATIVE TO SAID HOUSING, AND AN INWARDLY OPENING CHECK VALVE INEACH OF SAID HOUSING BYPASS PORTS, WHEREBY FLUID IS PERMITTED TO PASSINWARDLY THROUGH SAID HOUSING BYPASS PORTS AND OUT THE BOTTOM OF THETOOL TO EQUALIZE THE PRESSURE ABOVE AND BELOW SAID PACKER, AND WHEREBYFLUID MAY BE PUMPED DOWN THROUGH SAID STRING OF WELL TUBING AND OUT OFTHE BOTTOM OF SAID TOOL TO APPLY PRESSURE TO THE BOTTOM OF SAID PACKERTO AID IN UNSEATING THE SAME WITHOUT PASSING OUTWARDLY THROUGH SAIDHOUSING BYPASS PORTS.